U.S. patent application number 11/549285 was filed with the patent office on 2007-06-14 for reservoir with refill inlet for hand-held spray guns.
This patent application is currently assigned to 3M Innovative Properties Company. Invention is credited to Michael J.R. Adams, Antonio Bacciocchi, Malcolm F. Douglas, Stephen C.P. Joseph, Daniel E. Siltberg.
Application Number | 20070131793 11/549285 |
Document ID | / |
Family ID | 32870935 |
Filed Date | 2007-06-14 |
United States Patent
Application |
20070131793 |
Kind Code |
A1 |
Joseph; Stephen C.P. ; et
al. |
June 14, 2007 |
RESERVOIR WITH REFILL INLET FOR HAND-HELD SPRAY GUNS
Abstract
A paint reservoir has a fluid outlet 115 connectable to a spray
gun 101 and a fluid inlet 131 provided with a removable screw cap
132 whereby the fluid inlet 131 is directly accessible for
introducing paint to the reservoir while attached to the spray gun
101. The fluid outlet 115 and fluid inlet 131 may both be provided
in an end wall of the reservoir with outlet 115 located on the
longitudinal axis of the reservoir or offset to allow the size of
the fluid inlet 131 to be increased for easier filling of the
reservoir. The outlet 115 can be aligned with the longitudinal axis
of the reservoir or it can be inclined relative to the longitudinal
axis to provide greater clearance for access to the fluid inlet 131
when the reservoir is attached to the spray gun 101. In an
alternative arrangement, the fluid outlet is provided in an end
wall of the reservoir and the fluid inlet is provided in a sidewall
of the reservoir.
Inventors: |
Joseph; Stephen C.P.;
(Woodbury, MN) ; Adams; Michael J.R.; (Norfolk,
GB) ; Bacciocchi; Antonio; (Gerenzano, IT) ;
Douglas; Malcolm F.; (Swansea, GB) ; Siltberg; Daniel
E.; (White Bear Township, MN) |
Correspondence
Address: |
3M INNOVATIVE PROPERTIES COMPANY
PO BOX 33427
ST. PAUL
MN
55133-3427
US
|
Assignee: |
3M Innovative Properties
Company
|
Family ID: |
32870935 |
Appl. No.: |
11/549285 |
Filed: |
October 13, 2006 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
|
10475397 |
Mar 31, 2004 |
7188785 |
|
|
PCT/US02/13165 |
Apr 24, 2002 |
|
|
|
11549285 |
Oct 13, 2006 |
|
|
|
Current U.S.
Class: |
239/302 ;
239/323; 239/327; 239/328 |
Current CPC
Class: |
B05B 7/2478 20130101;
B05B 7/2481 20130101; B05B 7/2408 20130101 |
Class at
Publication: |
239/302 ;
239/323; 239/327; 239/328 |
International
Class: |
A62C 13/62 20060101
A62C013/62; B05B 9/047 20060101 B05B009/047; B65D 1/32 20060101
B65D001/32; B05B 11/04 20060101 B05B011/04 |
Foreign Application Data
Date |
Code |
Application Number |
Apr 24, 2001 |
GB |
0110025.4 |
Claims
1. Apparatus such as a spray gun for spraying a liquid comprising a
collapsible reservoir for a liquid to be sprayed, a spray nozzle
for dispensing liquid supplied from the reservoir, the reservoir
having a fluid outlet connectable to the apparatus and a fluid
inlet for adding liquid to the reservoir, and the fluid inlet
having a removable closure for opening and closing the fluid inlet,
wherein the closure is directly accessible when the reservoir is
connected to the apparatus.
2. Apparatus according to claim 1 wherein the reservoir comprises a
collapsible portion for the liquid to be supplied to the spray gun
and an attachment portion provided with the fluid outlet for
connecting the reservoir to the spray gun.
3. Apparatus according to claim 2 wherein the attachment portion is
adapted for releasably connecting the fluid outlet to the
apparatus.
4. Apparatus according to claim 3 wherein the attachment portion
and apparatus are provided with co-operating formations for
releasably securing the reservoir to the apparatus.
5. Apparatus according to claim 4 wherein the co-operating
formations are engageable with a push-twist action.
6. Apparatus according to claim 2 wherein the collapsible portion
comprises a flexible container for the liquid and the attachment
portion comprises a lid arranged to close an opening in the
container.
7. Apparatus according to claim 6 wherein the lid is separate from
the flexible container and means is provided for securing the lid
to close the opening in the container.
8. Apparatus according to claim 6 wherein the lid and flexible
container are permanently joined together.
9. Apparatus according to claim 6 wherein means is provided for
supporting the flexible container.
10. Apparatus according to claim 6 wherein the lid has an end wall
and a sidewall extending from the end wall, the sidewall being
arranged to connect the lid to the flexible container.
11. Apparatus according to claim 1 wherein fluid inlet is provided
with a spout and the removable closure comprises a screw cap
releasably engageable with a threaded portion of the spout.
12. A spray gun for spraying paint-like materials comprising a
spray nozzle for spraying a liquid, a collapsible reservoir for the
liquid, the reservoir having a fluid outlet releasably connected to
the spray gun whereby, after use, the reservoir can be detached and
discarded, and the reservoir further having a fluid inlet arranged
to be directly accessible when the reservoir is attached to the gun
for adding liquid to the reservoir.
13. A spray gun according to claim 12 of the gravity fed or
pressure fed type.
Description
CROSS REFERENCE TO RELATED APPLICATIONS
[0001] This is a continuation of application Ser. No. 10/475,397,
filed Apr. 24, 2002; which was a national stage filing under 35
U.S.C. 371 of PCT/US02/13165 filed Apr. 24, 2002, which
International Application was published by the International Bureau
in English on Oct. 31, 2002, which claims priority to GB 0110025.4,
filed Apr. 24, 2001, the disclosure of which is incorporated by
reference in their entirety herein.
FIELD
[0002] This invention concerns improvements in or relating to
liquid spraying apparatus. The invention has particular, but not
exclusive, application to hand held spray guns provided with a
liquid reservoir for spraying a substrate.
BACKGROUND
[0003] Spray guns are widely used in vehicle body repair shops when
re-spraying a vehicle that has been repaired following an accident.
In the known spray guns, the liquid is contained in a reservoir
attached to the gun from where it is fed to a spray nozzle. On
emerging from the spray nozzle, the liquid is atomised and forms a
spray with compressed air supplied to the nozzle. The liquid may be
gravity fed, suction fed or, more recently, pressure fed by an air
bleed from the compressed air source to the reservoir.
[0004] A typical paint finish may require application of a primer,
base coat and top coat. The spray gun and reservoir have to be
thoroughly cleaned when changing the liquid in the paint pot to
avoid cross-contamination which may adversely affect the finish.
This is especially important when spraying part of a vehicle to
match exactly the colour of the existing colour of the adjacent
bodywork.
[0005] Cleaning the spray gun and reservoir is time consuming and
often requires the use of solvents that are costly and may present
a health hazard to the operator. In order to reduce the amount of
cleaning and to facilitate changeover from one liquid to another,
we have previously proposed in WO 98/32539 an arrangement in which
the liquid is contained in a collapsible reservoir that functions
as a disposable lining for a paint pot.
[0006] In one construction, the reservoir comprises an open-ended
container that is a close fit in the paint pot, and a separate lid
that closes the open end of the container and has an outlet
connectable to the spray gun. In use, the container collapses as
the liquid is withdrawn and, after spraying, the container can be
removed from the paint pot with the lid attached and thrown away.
The paint pot can then be provided with a new, clean container for
a different liquid to be applied as the next coat. As a result, the
amount of cleaning required is considerably reduced and the spray
gun can be readily adapted to apply different liquids in a simple
manner.
[0007] With this arrangement, the reservoir has to be detached from
the spray gun and the lid removed if it is desired to top-up the
reservoir with more liquid. For example when painting a large area
or applying several coats of the same liquid to the same or
different vehicles such as when using a primer or lacquer finish.
This is time consuming and can be messy if the liquid is spilt.
Also, detaching the reservoir from the spray gun and removing the
lid to add more liquid to the reservoir increases the risk of
contamination from other sources, e.g. dust or dirt. Unwanted solid
particles can be removed by the inclusion of a filter but this may
become blocked and does not prevent the colour of the finish being
adversely affected by any contaminants being absorbed into the
liquid.
[0008] Another arrangement for lining a paint pot to reduce the
amount of cleaning is disclosed in U.S. Pat. No. 5,582,350. In this
arrangement, the paint is contained in a collapsible bag within the
paint pot and is connectable via an outlet at one end of the pot to
a spray gun. The other end of the pot is closed by a lid that is
removable to provide access to the bag within the pot. The bag has
a re-sealable zipper closure by means of which paint can be added
to the bag. The bag is initially connected to the outlet while
empty. Paint is then poured into the bag and the bag sealed before
securing the lid to close the pot. On completion of spraying, the
bag can be removed for disposal and replaced by a new clean bag.
With this arrangement there is a risk of spillage if the bag is
overfilled before fastening the zipper closure. Furthermore, if it
is desired to add paint to the bag in use, access to the zipper
closure is only possible if the lid is removed to open the pot.
Moreover, a collapsed or partially collapsed bag may have to be
extended before opening the zipper closure to add paint and the bag
may be disconnected from the outlet. As a result, paint may leak
from the bag necessitating cleaning of the pot when the bag is
removed on completion of spraying. This arrangement is therefore
generally only suitable for single use in which the bag is filled
once on initial set-up of the spray gun and is not intended for
re-filling the bag.
SUMMARY
[0009] The present invention is intended to improve further our
existing system and provide additional benefits and advantages for
the manufacturer and/or user.
[0010] More specifically, the present invention provides an
apparatus for spraying a liquid contained in a reservoir wherein
the liquid can be added to the reservoir without detaching the
reservoir from the apparatus.
[0011] In addition the present invention provides a collapsible
reservoir for connecting to spraying apparatus wherein the
reservoir can be supplied empty or pre-filled with liquid.
[0012] The present invention also provides a collapsible reservoir
for use with spraying apparatus which can be refilled in a simple
manner while attached to the apparatus and is disposable after use
to reduce the amount of cleaning required.
[0013] Other objects, benefits and advantages of the invention are
referred to later herein.
[0014] According to a first aspect of the present invention, there
is provided an apparatus such as a spray gun for spraying a liquid
comprising a collapsible reservoir for a liquid to be sprayed, a
spray nozzle for dispensing liquid supplied from the reservoir, the
reservoir having a fluid outlet connectable to the apparatus and a
fluid inlet for adding liquid to the reservoir, and the fluid inlet
having a removable closure for opening and closing the fluid inlet,
wherein the closure is directly accessible when the reservoir is
connected to the apparatus.
[0015] By the provision of a separate fluid inlet with a removable
closure that is directly accessible when the reservoir is connected
to the apparatus, liquid can be added to the reservoir without
removing the reservoir from the apparatus. This is of particular
benefit if the capacity of the reservoir is less than the volume of
paint required to paint a given area. Thus, when painting a large
area, the user can simply top-up the reservoir with additional
paint as required with the reservoir still attached to the
apparatus. As a result, the risk of spillage and/or contamination
of the paint is reduced. It is also of benefit when applying a
finishing clearcoat such as lacquer where the addition of solvent
to the reservoir to reduce the viscosity of the clearcoat for
`fading-out or blending` is made considerably easier.
[0016] Advantageously, the reservoir is adapted for releasable
connection to the apparatus. For example, the reservoir and
apparatus may be provided with co-operating formations for
releasably securing the reservoir. The co-operating formations may
be engageable with a push/twist action such as bayonet type
formations. In this way, the reservoir can be connected to and
released from the apparatus gun in a simple manner requiring
minimum effort or manual dexterity by the user.
[0017] The reservoir may comprise a collapsible portion for the
liquid to be supplied to the apparatus and an attachment portion
provided with the fluid outlet for connecting the reservoir to the
apparatus. For example, the collapsible portion may comprise a
flexible container for the liquid and the attachment portion may
comprise a lid arranged to close an opening in the container.
Preferably, the container and lid are disposable and can be thrown
away after use.
[0018] In one arrangement, the fluid outlet and fluid inlet are
provided in the lid at one end of the reservoir, and the fluid
inlet is constructed and arranged to be accessible when the
reservoir is connected to the apparatus via the fluid outlet. In
this way, the provision of the fluid inlet does not interfere with
collapsing of the reservoir as the liquid is being withdrawn.
Furthermore, by providing the fluid inlet and fluid outlet at the
end of the reservoir, the apparatus can be arranged to position the
fluid inlet to allow the reservoir to be substantially completely
filled. In addition, the fluid outlet may be positioned above the
level of the liquid in the reservoir. Moreover by having the fluid
inlet in the lid, it may be possible to insert a rod or other tool
for stirring the liquid in the reservoir thereby ensuring thorough
mixing of the added liquid with any liquid remaining in the
reservoir for continued spraying. Shaking is also possible to
ensure thorough mixing.
[0019] The fluid outlet may be arranged on a central longitudinal
axis of the reservoir but more preferably, the fluid outlet is
offset to one side of the central longitudinal axis. The offset
arrangement provides more room to accommodate the fluid inlet and
allows the fluid inlet to be enlarged. In this way, filling the
reservoir through the fluid inlet is facilitated with less risk of
spillage and a removable filter can be positioned in the fluid
inlet to filter the liquid as it is being introduced. As a result,
it may not be necessary to provide a filter within the reservoir to
filter the liquid as it is withdrawn from the reservoir through the
fluid outlet thereby reducing the risk of the flow of liquid being
restricted by blockages during spraying. The fluid inlet may be
accommodated inwardly of the marginal edge of the lid or it may
extend outwardly beyond the marginal edge.
[0020] The fluid outlet may extend parallel to the longitudinal
axis of the reservoir but more preferably the fluid outlet is
inclined relative to the longitudinal axis. Inclining the fluid
outlet provides greater clearance between the apparatus and the
fluid inlet so that access to the fluid inlet is improved when the
reservoir is attached to the apparatus.
[0021] The lid may be separate from the flexible container and
means provided for securing the lid to close the opening in the
container. In one arrangement, the flexible container is a close
fit in and provides a lining for an outer pot and the lid is
releasably secured to the container by a engagement of a locking
collar with the outer pot. In this way, the outer pot supports the
flexible container and enhances stability of the reservoir when
connected to the apparatus. Moreover, after use, the flexible
container and lid may be thrown away and the outer pot retained for
assembly with a new, clean flexible container and lid. As a result,
the amount of cleaning required is reduced.
[0022] In another arrangement, the lid and flexible container may
be bonded together by adhesive, welding or the like. Alternatively
or additionally, the lid and flexible container may be mechanically
secured together via engagement of interlocking formations or the
like. In this way, the reservoir may be supplied empty for filling
by the user via the fluid inlet or it may be pre-filled with a
liquid ready for the user to attach to the apparatus. A cage or
other form of external support may be provided for the flexible
container to improve stability of the reservoir when attached to
the apparatus.
[0023] Where the reservoir is supplied empty, it may be collapsed
to a compact form for storage and transportation. Pre-filling may
be employed for liquids that can be packaged and stored until
required without degrading. Thus, pre-filling may be especially
useful for liquids that can be supplied ready to use (i.e. without
requiring modification to match the colour to an existing colour).
For example, base coats in standard colours of a specified shade
and/or primers or lacquers that can be supplied in a non-activated
form and activated (if necessary) by suitable means such as by
exposure to a source of light (ultraviolet) or electrical energy
when required. Whichever arrangement is employed, the reservoir can
be re-filled in use without detaching from the apparatus by the use
of the fluid inlet.
[0024] In yet another arrangement, the lid has an end wall and a
sidewall extending from the end wall, the sidewall being arranged
to connect the lid to the flexible container either releasably or
permanently as described above. With this arrangement, the fluid
outlet may be provided in the end wall with the fluid inlet being
provided in the sidewall. In this way, access to the fluid inlet
may be enhanced and the inlet does not interfere with the collapse
of the flexible container in use of the reservoir. A set of lids
with sidewalls of different length may be provided for assembly
with a common flexible container whereby reservoirs of different
volume may be produced by selection of the appropriate lid.
[0025] In a still further arrangement, the reservoir includes a
sleeve extending between and connecting the lid and flexible
container. With this arrangement, the fluid outlet may be provided
in the lid at the end of the reservoir with the fluid inlet being
provided in the sleeve. A set of sleeves of different length may be
provided for assembly with a common flexible container and lid such
that the volume of the reservoir may be altered by selection of the
appropriate sleeve. Also, the reservoir may be assembled without
the sleeve if a fluid inlet is not required. Alternatively, the lid
may be provided with a fluid inlet as described previously.
[0026] The liquid may be filtered to remove unwanted solid
particles when filling the reservoir. Alternatively, the reservoir
may include a filter for removing unwanted solid particles from the
liquid supplied to the apparatus via the fluid outlet. Where a
filter is provided in the reservoir, the fluid inlet is arranged to
introduce liquid into the reservoir on the opposite side of the
filter to the fluid outlet. In this way, fluid added to the
reservoir via the fluid inlet must pass through the filter before
reaching the fluid outlet. As a result, unwanted solid particles,
i.e. contaminants, introduced with the liquid added to the
reservoir are retained within the reservoir and thrown away with
the container and lid.
[0027] Preferably, the fluid inlet comprises an opening closed by a
removable closure such as a screw cap. The opening may be provided
in a tubular spout portion projecting from the reservoir with the
screw cap releasably secured thereto. In this way, the cap can be
unscrewed to open the fluid inlet so that liquid can be added to
the reservoir when required and the cap re-attached to close the
inlet to continue spraying without removing the reservoir from the
apparatus.
[0028] According to another aspect of the present invention, there
is provided a spray gun for spraying paint-like materials
comprising a spray nozzle for spraying a liquid, a collapsible
reservoir for the liquid, the reservoir having a fluid outlet
releasably connected to the spray gun whereby, after use, the
reservoir can be detached and discarded, and the reservoir further
having a fluid inlet arranged to be directly accessible when the
reservoir is attached to the gun for adding liquid to the
reservoir.
[0029] The spray gun may be of the gravity fed or pressure fed
type.
[0030] According to a further aspect of the present invention,
there is provided a reservoir for supplying a liquid to a spray gun
or the like, the reservoir having a fluid outlet and a separate
fluid inlet, the reservoir being adapted for releasable connection
of the fluid outlet to the spray gun such that the fluid inlet is
directly accessible for introducing liquid to the reservoir while
attached to the spray gun, wherein the reservoir is collapsible
when liquid is withdrawn therefrom in use of the spray gun.
[0031] The reservoir may be pre-filled with liquid to be sprayed
with the fluid inlet permitting liquid to be added to the reservoir
in use without detaching the reservoir from the spray gun.
Alternatively, the reservoir may be supplied empty for the user to
fill with the liquid of their choice.
[0032] According to a still further aspect of the present
invention, there is provided a reservoir for attaching to a spray
gun, the reservoir having a fluid outlet for supplying liquid to
the spray gun and a separate fluid inlet for introducing liquid to
the reservoir, the fluid outlet being formed in an end wall of the
reservoir and the fluid inlet being formed in a sidewall of the
reservoir so as to be accessible when the fluid outlet is attached
to the spray gun.
[0033] The end wall may be a lid of the reservoir and the sidewall
may be a skirt integral with the lid or a separate sleeve connected
to the lid so that the fluid inlet is directly accessible when the
reservoir is connected to the spray gun. Preferably, the sidewall
extends between and connects the end wall to a flexible container
for the liquid that is collapsible as the liquid is withdrawn from
the reservoir in use. In this way, the fluid inlet does not
interfere with collapsing of the container in use.
[0034] According to yet another aspect of the present invention,
there is provided a reservoir for attaching to a spray gun, the
reservoir having a fluid outlet for supplying liquid to the spray
gun and a separate fluid inlet for introducing liquid to the
reservoir, the fluid outlet being formed in an end wall of the
reservoir and the fluid inlet being formed in the end wall offset
from the fluid outlet so as to be accessible when the fluid outlet
is attached to the spray gun.
[0035] The fluid outlet may be arranged on the central longitudinal
axis of the reservoir but more preferably the fluid outlet is
offset to one side of the longitudinal axis. The offset arrangement
provides more room to accommodate the fluid inlet which can be made
larger to facilitate filling the reservoir through the fluid
inlet.
[0036] The fluid outlet may extend parallel to the longitudinal
axis of the reservoir but more preferably the fluid outlet is
inclined relative to the longitudinal axis. The angled arrangement
increases the clearance between the spray gun and the fluid inlet
thereby improving access to the fluid inlet when the reservoir is
attached to the spray gun so that filling the reservoir through the
inlet is easier.
[0037] Preferably, the fluid inlet is directly accessible when the
reservoir is connected to the spray gun. Preferably, the reservoir
includes a collapsible container for the liquid and the end wall is
provided by a lid arranged to close an open end of the
container.
[0038] According to a still further aspect of the present
invention, there is provided a reservoir for attaching to a spray
gun, the reservoir having a container for a liquid, a lid for
closing the container, the lid having a fluid outlet connectable to
a spray gun, and a volume adaptor between the container and the
lid.
[0039] The volume adaptor may be an integral part of the lid, for
example a dependent skirt, or it may be separate from the lid and
container, for example a sleeve insertable between the lid and
container. In this way, the same container can be adapted to
provide the reservoir with any desired volume by selection and
fitment of the appropriate adaptor.
[0040] The adaptor may include a fluid inlet for adding liquid to
the reservoir while attached to the spray gun. For example, the
adaptor may be provided with a removable closure for the fluid
inlet.
[0041] The invention will now be described in more detail, by way
of example only, with reference to the accompanying drawings,
wherein:
BRIEF DESCRIPTION OF DRAWINGS
[0042] FIG. 1 is a perspective view of a prior art spray gun;
[0043] FIG. 2 is an exploded isometric view of the component parts
of the paint reservoir shown in FIG. 1;
[0044] FIG. 3 is a perspective view of the assembled paint
reservoir shown in FIG. 2;
[0045] FIG. 4 is a longitudinal section through the paint reservoir
shown in FIG. 3;
[0046] FIG. 5 shows separation of the component parts of the paint
reservoir of FIG. 3 after use.
[0047] FIG. 6 is a perspective view of an adapter for connecting
the paint reservoir to the spray gun;
[0048] FIG. 7 is a longitudinal section through the adapter shown
in FIG. 6;
[0049] FIG. 8 is an exploded isometric view similar to FIG. 2
showing the component parts of a paint reservoir according to a
first embodiment of the invention;
[0050] FIG. 9 is a perspective view similar to FIG. 3 showing the
assembled paint reservoir of FIG. 8;
[0051] FIG. 10 is a longitudinal section through the paint
reservoir of FIG. 9;
[0052] FIG. 11 is a perspective view showing the reservoir of FIGS.
8 to 10 attached to the spray gun of FIG. 1 with the spray gun
shown inverted and the closure cap removed for adding paint to the
reservoir;
[0053] FIG. 12 is a perspective view of the spray gun shown in FIG.
11 re-inverted and ready for use;
[0054] FIG. 13 is a longitudinal section of an alternative lid and
filter for the reservoir shown in FIGS. 8 to 12;
[0055] FIG. 14 is a longitudinal section showing an alternative
location of the fluid inlet and closure cap for the reservoir shown
in FIGS. 8 to 12;
[0056] FIG. 15 is a longitudinal section showing yet another
location of the fluid inlet and closure cap for the reservoir shown
in FIGS. 8 to 12;
[0057] FIG. 16 is a perspective view of a paint reservoir according
to a second embodiment of the invention;
[0058] FIG. 17 shows the paint reservoir of FIG. 16 in a collapsed
condition;
[0059] FIG. 18 shows a modification to the paint reservoir shown in
FIG. 16 to include a support cage;
[0060] FIG. 19 shows an alternative support cage for the paint
reservoir shown in FIG. 16;
[0061] FIG. 20 shows a modification of the paint reservoir shown in
FIG. 16;
[0062] FIG. 21 is a longitudinal section of a paint reservoir
according to a third embodiment of the invention;
[0063] FIG. 22 is a perspective view of the paint reservoir of FIG.
21 with the closure cap removed;
[0064] FIG. 23 is a plan view of the paint reservoir of FIG.
21;
[0065] FIG. 24 is a perspective view showing the paint reservoir of
FIGS. 21 to 23 connected to the spray gun of FIG. 1 with the spray
gun shown inverted and the closure cap removed for adding paint to
the reservoir;
[0066] FIG. 25 is a longitudinal section of an alternative lid for
the paint reservoir shown in FIG. 21;
[0067] FIG. 26 is a perspective view of the lid shown in FIG. 25
with the closure cap removed;
[0068] FIG. 27 is a plan view of the lid shown in FIG. 25;
[0069] FIG. 28 is a longitudinal section of a paint reservoir
according to a fourth embodiment of the invention;
[0070] FIG. 29 is a longitudinal section of the lid of the paint
reservoir shown in FIG. 28;
[0071] FIG. 30 is a perspective view of the paint reservoir shown
in FIG. 28;
[0072] FIG. 31 is a perspective view showing the lid of FIG. 29
attached to a spray gun to form a reservoir for paint;
[0073] FIG. 32 is a longitudinal section showing a modification to
the paint reservoir of FIG. 28;
[0074] FIG. 33 is a perspective view of the paint reservoir shown
in FIG. 32; and
[0075] FIG. 34 is a perspective view, similar to FIG. 33, showing
an alternative arrangement for the fluid inlet.
DETAILED DESCRIPTION
[0076] FIG. 1 of the drawings illustrates a prior art paint spray
gun 1 of the gravity-feed type disclosed in our co-pending patent
application published under No: WO 98/32539 the contents of which
are incorporated herein by reference.
[0077] The gun 1 comprises a body 2, a handle 3 which extends
downwards from the rear end of the body, and a spray nozzle 4 at
the front end of the body. The gun 1 is manually-operated by a
trigger 5 which is pivotally-mounted on the sides of the gun.
[0078] A paint reservoir 6, which contains paint (or similar
material) to be discharged by the gun, is located on the top of the
body 2 and communicates with an internal passageway (not visible)
which extends through the gun to the nozzle 4.
[0079] In use, the gun 1 is connected via a connector 7 at the
lower end of the handle 3 to a source of compressed air (not shown)
so that, when the user pulls on the trigger 5, compressed air is
delivered through the gun to the nozzle 4. As a result, paint
delivered under gravity from the paint pot 6 to the nozzle 4 is
atomised on leaving the nozzle 4 and forms a spray with the
compressed air emerging from the nozzle 4.
[0080] Referring now to FIGS. 2 to 4 of the drawings, the paint pot
6 includes an outer container 8, a disposable inner container 9, a
disposable lid 10, and a collar 11. The inner container 9
corresponds in shape to (and is a close fit in) the interior of the
outer container 8 and has a narrow rim 12 at the open end which
sits on the top edge of the container 8.
[0081] The lid 10 has a dependent skirt 13 which is a push-fit in
the open end of the inner container 9 and a central aperture 14
from which extends a connector tube 15 forming a fluid outlet. The
tube 15 is provided at its free end with outward extensions 16
forming one part of a bayonet connection. The aperture 14 is
covered by a filter mesh 17 which may be a push fit into the
aperture 14 or may be an integral part of the lid 10.
[0082] The skirt 13 is inset from the outer edge of the lid 10 and
the rim 12 of the inner container 9 is trapped between the end of
the outer container 8 and the outer edge of the lid 10. The lid 10
is held firmly in place on the container 8 by the annular collar 11
that screws onto the container 8 on top of the lid 10. In the
assembled condition, the inner container 9 and lid 10 form a
reservoir for containing the paint or other liquid to be delivered
to the nozzle 4 via the connector tube 15.
[0083] The paint pot 6 is attached to the spray gun 1 through use
of an adapter 18 shown separated from the paint pot 6 in FIG. 6.
The adapter 18 is a tubular component which is formed internally at
one end 19 with the other part of the bayonet connection for
attachment to the connector tube 15 of the lid 10. At the other end
20, the adapter 18 is shaped to match the standard attachment of
the spray gun paint pot (typically a screw thread).
[0084] The container 8 of the paint pot 6 is formed from a plastic
material, for example polyethylene or polypropylene, and may be
translucent (as shown in FIG. 2) or opaque, and of any suitable
size. For use with a paint spray gun, containers 8 having a
capacity of 250, 500 or 800 ml could typically be used, although
other sizes could be used if required.
[0085] In this embodiment, the container 8 is of generally
cylindrical shape closed at one end 8A. The other end is open and
side wall 8B is formed with an external screw thread 8C. Base 8A is
flat so that the container 8 can stand unsupported on a flat
surface and is formed with a central air hole 8D. Internally, the
side wall 8B tapers inwardly slightly from the open end to the base
8A.
[0086] The inner container 9 is preferably transparent and is
thermo-formed from a single piece of plastics material, preferably
polyethylene or polypropylene. The shape of the inner container 9
is dictated by and matches the internal shape of the container 8.
The inner container 9, like the inside of the container 8, is of
generally cylindrical shape closed at one end 9A and side wall 9B
tapers inwardly slightly from the mouth towards the closed end
9A.
[0087] The rim portion 12 and base or closed end 9A are
comparatively rigid but the side walls 9B are flexible and can be
made to collapse. Nevertheless, the inner container 9 is capable of
standing, unsupported, on the base 9A with side walls 9B extended
and upright as shown in FIGS. 2 to 4.
[0088] When the inner container 9 collapses, the comparatively
rigid base 9A retains its form but moves towards the rim portion 12
as a consequence of the collapse of the side walls 9B, as
illustrated in FIG. 5. The side walls 9B collapse in a similar
fashion to a plastic bag without being ruptured (e.g. by splitting,
tearing or cracking).
[0089] In one form, the inner container 9 has a height of about 110
mm, a diameter at its base 9A of about 78 mm and a diameter at its
mouth (excluding the rim portion 12) of about 86 mm. The base 9A
has a thickness of about 400 .mu.m, the rim portion 12 has a
thickness of about 900 .mu.m, and the side walls 9B have a
thickness of about 150 .mu.m.
[0090] In another form, the inner container 9 has the same height
and the same diameters at its base 9A and mouth but the base 9A has
a thickness of about 300 .mu.m, the rim portion 12 has a thickness
of about 200 .mu.m and the side walls 9B have a thickness in the
range of from 50 to 250 .mu.m.
[0091] The lid 10 is also formed from a plastic material, for
example, polyethylene or polypropylene, and may be formed by an
injection moulding process. The lid 10 may be translucent or opaque
and may be coloured. The collar 11 may be a moulded plastic
component, or it may be a machined metal (for example, aluminium)
component. The adapter 18 may be a metal or plastic component and
may, for example, be formed from aluminium and anodised or
plated.
[0092] To use the paint pot 6, the adapter 18 is attached at the
end 20 to the spray gun and is left in position. Then, with the
paint pot 6 disassembled as shown in FIG. 2, the inner container 9
is pushed inside the outer container 8. Paint is then put into the
inner container 9 and, if necessary, mixed with other tinters,
hardeners and thinners (solvents). The lid 10 is then pushed into
place and the collar 11 is screwed down tightly to hold the lid 10
in position.
[0093] The top portion of the inner container 9 is then trapped
between the skirt 13 of the lid 10 and the sidewall 8B of the
container 8, and the rim 12 of the inner container 9 is trapped
between the top edge of the container 8 and the collar 11 as shown
in FIG. 4.
[0094] The spray gun 1 is then inverted from its normal operating
position illustrated in FIG. 1. The end of the connector tube 15
can then be attached to the adapter 18 without spilling the paint
contained in the reservoir by a simple push/twist action to engage
the co-operating bayonet formations. The spray gun 1 can then be
returned to its normal operating position for use in the usual
way.
[0095] As paint is removed from within the inner container 9, the
sides 9B of the inner container 9 collapse as a result of the
decreased pressure within the inner container 9. The base 9A of the
inner container 9, being more rigid, retains its shape so that the
inner container 9 tends to collapse in the longitudinal rather than
the transverse direction thereby reducing the possibility of
pockets of paint being trapped in the inner container 9.
[0096] The user can choose to evacuate the air from within the
inner container 9 before operating the spray gun 1 although that is
not essential. It does, however, increase the range of angles at
which the spray gun 1 will function satisfactorily since there is
no risk of air entering the spray gun 1 from the paint pot 6. To
evacuate the air from within the inner container 9, the trigger 5
of the spray gun 1 should be actuated while the spray gun 1 is
still in the inverted position.
[0097] After use, when the spray gun 1 is to be cleaned, the spray
gun 1 can be re-inverted from its operating position shown in FIG.
1. The airline is disconnected and the trigger 5 actuated briefly
to allow paint within the spray gun 1 to drain back into the inner
container 9 in the pot 6. The pot 6 is then removed from the spray
gun 1 by disengaging the bayonet formations and detaching the
connector tube 15 from the adapter 18 which remains on the spray
gun 1.
[0098] As will be appreciated, the bayonet formations provide a
connector system that enables the pot 6 to be quickly connected to
and removed from the spray gun 1 with a simple push-twist action
requiring less manual dexterity than a threaded connection. It will
be understood, however, that any other type of connector system may
be employed to releasably connect the pot 6 to the spray gun 1.
[0099] The collar 11 is removed from the outer container 8, and the
lid 10 is then pulled out, bringing with it the collapsed inner
container 9 as shown in FIG. 5. The lid 10 (including the filter
17) and inner container 9 are discarded, leaving the outer
container 8 and collar 11 clean and ready for re-use with a fresh
inner container 9 and lid 10. Only the spray gun 1 itself needs to
be cleaned, resulting in a substantial reduction in the amount of
solvent used.
[0100] The risk of unused paint spilling from the pot 6 is also
substantially reduced because the inner container 9 is removed and
discarded in a somewhat collapsed condition with the lid 10 in
place. Moreover, because the inner container 9 is discarded in a
collapsed condition, the amount of space required for collection of
used inner containers 9 is minimised.
[0101] Because the inner container 9, as described above, is an
accurate fit inside the outer container 8 and has a smooth internal
surface, it is possible to mix paint in the inner container 9
within the outer container 8 rather than in a separate receptacle.
In that way, cleaning of a separate mixing receptacle can also be
eliminated to achieve a further reduction in the amount of solvent
used.
[0102] The general shape of the outer container 8 and, in
particular the fact that it is flat-bottomed and stable when in the
orientation shown in FIG. 2, makes it particularly suitable for
mixing paint in the inner container 9 supported within the
container 8.
[0103] The possibility of the inner container 9 being punctured or
damaged by the mixing implement is minimised. First because the
inner container 9 fits inside the outer container 8 exactly and,
second, because the self-supporting nature of the inner container 9
means that it is less likely to be dragged around inside the outer
container 8 during the mixing process.
[0104] To facilitate the use of the inner container 9 as a mixing
receptacle, the outer container 8 is translucent and the sidewall
8B provided with markings 21 (FIG. 2) for indicating the volume of
the contents of the inner container 9. Alternatively, if the outer
container 8 is opaque, it could be formed with slots in the
sidewall 8B through which the inner container 9 could be viewed to
enable the user of the spray gun 1 to assess the amount of paint in
the pot 6 at any time.
[0105] When paint is mixed in the inner container 9, the inclusion
of the filter mesh 17 in the lid 10 prevents unwanted particles in
the paint from entering the spray gun 1. The mesh 17 can be
omitted, however, if the paint is textured, or if it is mixed in a
separate receptacle and strained when it is transferred to the
inner container 9 or if the presence of contaminants in the paint
is unimportant.
[0106] As will be apparent from the foregoing description, the
arrangement of the disposable inner container 9 and lid 10 to form
a reservoir containing the paint or other liquid to be sprayed,
considerably reduces the amount of cleaning required when changing
the liquid to be sprayed or when putting the spray gun 1 away at
the end of the working day.
[0107] It can happen, however, that the area to be painted requires
a larger volume of paint than the reservoir can hold. In these
circumstances, the user has to remove the pot 6 from the spray gun
1, release the collar 11 and remove the lid 10 to allow the
reservoir to be topped up. The lid 10 then has to be relocated on
the open end of the inner container 9, the collar 11 refitted and
the pot 6 reattached to the spray gun 1 to enable the user to
continue spraying. This is time consuming and there is a risk of
paint being spilt and/or contaminated when the lid 10 is
removed.
[0108] As an alternative to re-filling the reservoir, some users
fill two or more reservoirs with the same liquid that can be fitted
to the spray gun in turn when spraying large areas. Although, the
user can change over the reservoirs and continue spraying with the
same liquid, filling and assembling several reservoirs is time
consuming and adds to operating costs. Thus, each reservoir has a
disposable inner container and lid which is discarded after
spraying and using several reservoirs for the same liquid is
wasteful of such disposable items and requires the user to have
available a sufficient number of pots and collars for assembly of
the reservoirs.
[0109] Referring now to FIGS. 8 to 12 of the drawings, there is
shown a first embodiment of the present invention that enables the
user to add paint to the reservoir while attached to the spray gun.
For convenience, like reference numerals in the series 100 are used
throughout to indicate parts corresponding to FIGS. 1 to 7 and the
construction and operation of similar parts will be understood from
the description above and will not be further described in
detail.
[0110] As shown in FIGS. 8 to 10, the paint pot 106 comprises outer
container 108, inner container 109, lid 110 and collar 111. In
accordance with the present invention, the lid 110 is provided with
an opening 130 offset from the central connector tube 115. The
opening 130 is bounded by an external tubular spout portion 131
providing a fluid inlet that is closed by a removable cap 132
screwed onto the tubular spout portion 131.
[0111] The tubular spout portion 131 is formed integrally with the
lid 110 and has an external screw thread 133 for engagement by an
internal screw thread 134 of the cap 132. In this way, the cap 132
can be removed to allow access to the reservoir through the opening
130 in the lid 110 and re-secured to close the opening 130. The
screw cap 132 provides a simple method of opening and closing the
fluid inlet to allow liquid to be introduced into the reservoir. It
will be understood, however, that any arrangement for introducing
liquid to the reservoir may be employed which enables the fluid
inlet to be opened and closed when required.
[0112] With reference now to FIGS. 11 and 12, the tubular spout
portion 131 is arranged so that, when the pot 106 is secured to the
spray gun 101 and the spray gun 101 is inverted from its normal
operating position, the fluid inlet is at the upper end of the
reservoir (FIG. 11). In this way, the cap 132 can be removed and
paint or other liquid added to the reservoir through the fluid
inlet without removing the pot 106 from the spray gun 101. The cap
132 can then be re-attached and the spray gun 101 re-inverted to
its normal operating position to allow the user to continue
spraying (FIG. 12). The addition of liquid to the reservoir may be
facilitated by the use of a funnel to reduce the risk of spillage,
for example when pouring paint from another container.
Alternatively, the spout portion 131 may be extended by attaching a
flexible tube to facilitate addition of liquid to the reservoir via
the fluid inlet.
[0113] When it is desired to change the liquid in the reservoir,
the pot 106 is detached from the spray gun 101, and the inner
container 109 and lid 110 removed as a complete assembly and thrown
away as described above. A new, clean, inner container 109 can then
be fitted in the pot 106 and filled with the new liquid either
before or after fitting the lid 110 and securing the collar 111.
The pot 106 can then be attached to the spray gun 101 and, in use,
if the reservoir needs to be topped up, this can be done via the
fluid inlet by removing the cap 132 as described above.
[0114] Referring now to FIG. 13, this shows an alternative form of
lid 110' and filter 117' for use with the inner container 109 of
the previous embodiment. The lid 110' is of conical shape and the
filter 117' comprises a flat mesh screen that is push-fit within
the skirt 113' and is held in place by compression so as to extend
across the open end of the inner container 109 when the skirt 113'
is inserted into the inner container 109. This arrangement
increases the surface area of the filter 117' compared to the
previous embodiment in which the filter 117 fits over the end of
the connector tube 115. As a result, flow of paint is improved. In
a modification (not shown), the mesh screen is mechanically held in
place by engagement of the marginal edge of the screen with a rib,
groove or similar locating formation on the inside of the skirt
113'.
[0115] In accordance with the present invention, the lid 110' is
provided with an opening 130' in the conical wall offset from the
connector tube 115'. The opening 130' is bounded by external
tubular spout portion 131' on which closure cap 132' is releasably
secured. The tubular portion 131' extends at an angle away from the
connector tube 115' towards the peripheral edge of the lid 110'. As
a result, access for adding paint is enhanced.
[0116] In this modification, the opening 130' is above the filter
117' and the lid 110' is formed with an integral internal tubular
spout portion 135' extending from the opening 130' to an aligned
opening 136' in the filter 117'. In this way, paint added to the
reservoir via the opening 130' passes directly into the reservoir
without having to pass through filter 117'. As a result, if the
paint contains any particles or the like, these are removed by the
filter 117' and cannot pass through the connector tube 115' in use
of the spray gun 101.
[0117] Referring now to FIG. 14, this shows an alternative location
for the opening 130'' for adding paint to the reservoir with the
pot 106'' attached to the spray gun 101. The opening 130'' is
provided in the sidewall 109B'' of the inner container 109'' and
the outer container 108'' is provided with an opening 137'' through
which tubular spout portion 131'' extends to attach the closure cap
132''. The inner container 109'' can be collapsed to allow the
tubular spout portion 131'' to be inserted through the opening
137'' from within the container 108''. The cap 132'' may then be
attached or the opening may be large enough to allow the spout
portion 131'' to be inserted with the cap 132'' already
attached.
[0118] This arrangement of the fluid inlet on the side of the pot
106'' provides relatively free access to the cap 132'' when it is
desired to add paint to the reservoir. Preferably, the fluid inlet
is provided at the upper end of the inner container 109'' as shown.
In this way, it does not to interfere significantly with collapsing
of the reservoir when paint is withdrawn during spraying.
Furthermore, when it is desired to add paint to the reservoir with
the pot 106'' attached the spray gun 101, the reservoir can be
filled up to the level of the opening 130'' without spilling.
[0119] With reference now to FIG. 15, this shows yet another
possible location for the opening 130''' for adding paint to the
reservoir with the pot 106''' attached to the spray gun 101. The
opening 130''' is provided in base 109A''' of the inner container
109''' and the outer container 108''' is provided with an opening
138''' in the base through which tubular spout portion 131''' can
extend. In this case, the opening 138''' must be large enough for
the cap 132''' to pass freely through so as not to interfere with
collapsing of the inner container 109''' when paint is withdrawn
from the reservoir.
[0120] With this arrangement, paint may be added to the reservoir
with the pot 106''' attached to the spray gun 101 and the spray gun
101 in its normal operating position, i.e. the spray gun 101 does
not have to be inverted. When re-filling the reservoir, the
collapsed or partially collapsed inner container 109''' may have to
be manually extended
[0121] The sidewalls 108B''' of the container 108''' may be
extended below the base 108A''' to allow the pot 106''' to stand on
a flat surface with the inner container 109''' inserted and the
tubular portion 131''' extending through the opening 138''' in the
base 108A'''. Alternatively, the outer container 108''' may
comprise sidewalls 108B''' only with no base wall.
[0122] Referring now to FIGS. 16 and 17, a second embodiment of the
present invention is shown for adding paint or other liquid to the
reservoir while attached to the spray gun. For convenience, like
reference numerals in the series 200 are used throughout to
indicate parts corresponding to the previous embodiment and the
construction and operation of similar parts will be understood from
the description above and will not be further described in
detail.
[0123] In this embodiment, the inner container 209 is permanently
attached to the lid 210 which has a fluid outlet connectable to the
spray gun and a fluid inlet for adding paint to the reservoir. For
example, the lid 210 may be bonded to the inner container 209 by
adhesive or by welding.
[0124] This arrangement enables the construction of the reservoir
to be simplified compared to the previous embodiment. In
particular, the outer container for receiving the inner container
209 and the collar for securing the lid 210 are no longer required
for assembly of the reservoir and can be dispensed with.
[0125] In this embodiment, the materials employed for the container
209 and lid 210 are similar to the previous embodiment. It will be
understood, however, that this is not essential. Thus, the
container 209 can be constructed from any material that is
resistant to tearing, ripping or rupturing and which collapses as
paint is being withdrawn. For example, the container 209 may be
made of metal foil and/or metal foil may be incorporated into a
plastic laminate to provide the required characteristics for the
container 209.
[0126] The assembly of lid 210 and container 209 may be pre-filled
with a liquid and supplied to the user for attaching to the spray
gun 1 via the connector tube 215 on the lid 210. The reservoir can
then be refilled while still attached to the spray gun 1 via the
fluid inlet by removing the cap 232. Pre-filling may be employed
for liquids that can be packaged and stored until required without
degrading. Thus, pre-filling may be especially useful for liquids
that can be supplied ready to use (i.e. without requiring
modification to match the colour to an existing colour). For
example, base coats in standard colours and/or primers or lacquers
that can be supplied in a non-activated form and activated (if
necessary) by suitable means such as by exposure to a source of
light (ultraviolet) or electrical energy when required.
[0127] Alternatively, the assembly of lid 210 and container 209 may
be supplied empty for the user to fill with liquid via the fluid
inlet with the cap 232 removed. This enables the user to use either
standard liquids or liquids that have been specially mixed to match
a particular colour. Again, the reservoir can be refilled in use
while attached to the spray gun 1.
[0128] Where the assembly of container 209 and lid 210 is supplied
empty, the container 209 may be collapsed thereby reducing the
space required for packing and transportation of the assembly by
the manufacturer and the space required for storing the assembly
until required by the end user. Where the assembly is supplied and
stored in the collapsed condition, the container 209 can be
returned to its original shape prior to adding the chosen
liquid.
[0129] In this embodiment, the lid 210 and container 209 are
permanently secured together and the reservoir is sufficiently
stable for attaching to the spray gun without any additional
support. For some applications, however, it may be desirable or
necessary depending on the size and/or materials employed for the
container 209 to provide support for the container 209 when the
reservoir is attached to the spray gun.
[0130] FIGS. 18 and 19 show two support cages 280 and 281 that can
be employed to support the reservoir as the container 209
collapses. The cages 280, 281 are made of plastics material that
combine the necessary strength with lightness for ease of handling
the spray gun to which the reservoir with the cage 280, 281 is
attached. It will be understood, however, that other materials may
be employed.
[0131] In FIG. 18, the cage 280 provides support over the whole
length of the container 209' and is in the form of an open mesh
that allows visual inspection of the reservoir as the container
209' collapses. In FIG. 19, the cage 281 provides support over part
of the length of the container 209' and is in the form of a short
tube that may be transparent to allow visual inspection of the
reservoir as the container collapses. It will be understood however
that any suitable design of cage may be employed that adequately
supports the container 209'. For example, the cage may comprise a
plurality of downward extending leg portions for guiding the
container to collapse in the longitudinal direction.
[0132] In FIGS. 18 and 19, the cage 280, 281 is separate from the
lid 210' and container 209' and is secured by an annular collar 282
that fits over the lid 210'. It will be understood, however, that
the cage could be formed as an integral part of the lid 210'.
[0133] It will also be understood that the cage 280, 281 and collar
282 are not limited to arrangements in which the lid 210' and
container 209' are permanently attached together. Thus, the cage
280, 281 and collar 282 may be used in any of the arrangements
according to the first embodiment in which lid and container are
separate components to secure the lid and container together and
provide support for the reservoir as the container collapses.
[0134] Referring now to FIG. 20, an alternative arrangement is
shown for permanently uniting the lid 210'' and container 209'' in
which an annular groove 240 is provided in the underside of the lid
210'' to receive the rim 212'' of the container 209''. The rim
212'' and groove 240 are provided with complementary interlocking
formations to seal the lid 210'' on the container 209'' and prevent
the container 209'' separating from the lid 210''. This assembly
may be carried out during manufacture for supply of the lid 210''
and container 209'' pre-filled with liquid or empty as described
above. Alternatively, the lid 210'' and container 209'' may be
supplied separately for assembly by the user. This arrangement may
be provided with a support cage for the container as described
above. The cage may be a separate component or formed integrally
with the lid 210''. For example, the outer wall of the groove 240
may be extended axially to surround the container 209'' over all or
part of the length of the container 209''.
[0135] Referring to FIGS. 21 to 24, there is shown a third
embodiment of the present invention for adding paint to a reservoir
while attached to a spray gun. For convenience, like reference
numerals in the series 300 are used throughout to indicate parts
corresponding to previous embodiments and the construction and
operation of similar parts will be understood from the description
above and will not be further described in detail.
[0136] In this embodiment, the end wall of the lid 310 is of
conical shape and the connector tube 315 is offset from the centre
of the lid 310 and extends at an angle to the central longitudinal
axis of the lid 310. This offset arrangement allows the size of the
opening 330 to be increased compared to the previous embodiments.
As shown, the opening 330 has a diameter of slightly less than half
the diameter of the lid 310. It will be understood, however, that
the size of the opening 330 may be altered from that shown.
[0137] As will be appreciated, increasing the size of the opening
330 allows faster filling/refilling of the reservoir formed by
attaching the lid 310 to the container 309. Furthermore, a
removable "drop in" sock filter can be used in conjunction with the
opening 330 to filter paint poured into the reservoir. As a result,
there is no need to employ a filter over the aperture 314 of the
connector tube 315 when the reservoir is connected to a spray
gun.
[0138] Furthermore, as shown in FIG. 24, access to the opening 330
when the reservoir is attached to the spray gun 301 and the spray
gun 310 is inverted for adding paint to the reservoir is enhanced
by the offset arrangement of the connector tube 315 extending at an
angle relative to the longitudinal axis of the opening 330. As a
result, the opening 330 is clear of the spray gun 301 and paint can
be introduced more easily to the reservoir through the opening 330
with the reservoir attached to the spray gun. This contributes
further to faster filling of the reservoir with reduced risk of
spillage.
[0139] Depending on the starting/finishing positions of the bayonet
formations 316 for securing the reservoir to the spray gun 301, the
offset arrangement of the connector tube 315 may result in the
reservoir overhanging to one side of the spray gun 301. This could
have an adverse effect on the handling of the spray gun 301. In
particular, the spray gun 301 may be unbalanced making it more
awkward to manoeuvre and making access for spraying more difficult
where available space is restricted.
[0140] Accordingly, the bayonet formations 316 are arranged so
that, when the reservoir is connected to the spray gun 301, it is
aligned along the spray axis of the spray gun 301. In this way,
unbalance due to the reservoir overhanging to one side is avoided.
Additionally, the inclination of the connector tube 315 to the
longitudinal axis of the reservoir may be chosen so that the
reservoir is arranged at an optimum angle to the spray gun to best
suit working requirements. In this way, any adverse effects
resulting from the offset arrangement of the connector tube 315 on
handling of the spray gun 301 are overcome or at least
mitigated.
[0141] In this embodiment, the container 309 is permanently
attached to the lid 310 by adhesive, welding or any other suitable
method as described previously in connection with the second
embodiment of the invention. It will be understood, however, that
the advantages from offsetting the connector tube 315 and
increasing the size of the filler opening 330 may be applied to any
of the other lid/container combinations described herein. For
example, the lid may be separate from the container and secured by
a collar as described in connection with the first embodiment.
Furthermore, it will be appreciated the offset arrangement of the
connector tube 315 and increased size of the filler opening 330 may
be applied to any shape of lid. For example, the lid may have a
flat end wall as shown in FIGS. 8 to 17 or a conical end wall as
shown in FIGS. 18 to 24.
[0142] Referring now to FIGS. 25 to 27, an alternative arrangement
for increasing the size of the filler opening 330' in the lid 310'
to facilitate filling/re-filling the reservoir according to the
third embodiment of the invention is shown. The connector tube 315'
is positioned at the apex of the conical end wall of the lid 310'
aligned with the central longitudinal axis of the lid 310'. As a
result, the reservoir does not overhang to one side of the spray
gun irrespective of the start/finish position of the bayonet
formations 316' for securing the reservoir to the spray gun. To
accommodate the increased size of the filler opening 330' without
restricting access when the reservoir is attached to the spray gun,
the spout 331' is arranged to overhang the rim of the lid 310' on
one side. The wall of the spout 331' that overhangs the rim of the
lid 310' is formed with an angled portion 361' that directs paint
towards and through a substantially D-shaped aperture 360' leading
into the reservoir at the base of the opening 330'.
[0143] The lid 310' may be permanently attached to the container
309' as described previously or it may be separate from the
container 309' and secured by a suitably shaped collar as described
previously.
[0144] Referring now to FIGS. 28 to 30, a fourth embodiment of the
present invention for adding paint to a reservoir while attached to
a spray gun is shown. For convenience, like reference numerals in
the series 400 are used throughout to indicate parts corresponding
to previous embodiments and the construction and operation of
similar parts will be understood from the description above and
will not be further described in detail.
[0145] In this embodiment, the inner container 409 is received in
outer container 408 to locate the rim portion 412 over the outer
end of the container 408. The lid 410 has an elongated skirt 413 of
cylindrical shape integral with the end wall of the lid 410. The
free end of the skirt 413 is a push fit in the open end of the
inner container 409 to trap the rim portion 412 of the inner
container 409 between the end of the container 408 and an external
lip 413A integral with the skirt 413.
[0146] The end wall of the lid 410 is of conical shape and is
provided with the connector tube 415 and filler opening 430 for
filling/refilling the reservoir while connected to the spray gun as
described for the previous embodiment. In this embodiment, the
connector spout 415 is arranged on the central longitudinal axis of
the lid 410 but it will be understood the lid 410 may be provided
with any of the connector spout 415 and filler opening 430
arrangements previously described.
[0147] As will be appreciated, the elongated skirt 413 increases
the volume of the reservoir and allows the spray gun to be used for
large paint jobs without having to repeatably refill the reservoir
with paint. Furthermore, the same combination of outer container
408 and inner container 409 may be assembled with lids 410 having
different lengths of skirt 413 to provide reservoirs having a range
of different volumes. In this way, the required volume reservoir
for a particular job can be readily assembled by selecting the lid
410 having the appropriate size of skirt 413 and assembling the
selected lid 410 with the same combination of outer container 408
and inner container 409. As a result, the number of components
required to produce a range of reservoirs of different volume is
reduced. More particularly, the use of different size inner
containers 409 requiring different size outer containers 408 is
avoided such that manufacture, supply, storing and assembly of
components for assembly of reservoirs of different volume is
facilitated.
[0148] In a modification (not shown), the filler opening 430 may be
re-positioned from the end wall of the lid 410 and located in the
skirt 413 where permitted by the length of the skirt 413. This may
allow easier access to the filler opening 430 when the reservoir is
connected to the spray gun.
[0149] Referring now to FIG. 31, the lid 410 with elongated skirt
413 may be used by itself to provide a low volume reservoir for
small repair jobs, for example spot repairs. This may result in
cost savings by reducing the time taken to carry out a repair and
by reducing the number of disposable components required for the
repair from two to one where the lid 410 can be used without the
inner container 409.
[0150] A vented cover (not shown) can be used to close off the open
end of lid 410 with elongated skirt 413.
[0151] Referring now to FIGS. 32 and 33, an alternative arrangement
is shown for varying the volume of the reservoir in which a
separate sleeve 450 of cylindrical shape is provided between the
lid 410' and inner container 409'.
[0152] As shown, the short skirt 413' on the underside of the lid
410' is a push fit in one end of the sleeve 450 to locate the outer
edge of the lid 410' on the end of the sleeve 450. The other end of
the sleeve 450 is a push fit in the open end of the inner container
409' to trap rim portion 412' of the inner container 409' between
the end of the container 408' and an external lip 450A of the
sleeve 450. Locking collar 411' is threadably engageable with the
outer container 408 to secure the sleeve 450 relative to the inner
container 410'. The locking collar 411' is connected via axially
extending webs 451 to a retainer collar 452 that clamps the
separate lid 410' to the sleeve 450 as the locking collar 411' is
tightened.
[0153] As will be appreciated, the ends of the sleeve 450 are
shaped to co-operate with the inner container 409' and lid 410'
such that the inner container 410' and lid 409' can be assembled
either with or without the sleeve 450 therebetween. In this way,
the same inner container 409' and lid 410' combination can be
assembled with or without sleeves 450 of different length to
provide reservoirs having a range of different volumes.
[0154] More particularly, the lid 410' can be assembled directly to
the inner container 409' where the reservoir only has to hold a
small volume of paint. The same lid 410' and inner container 409'
can also be assembled with an appropriately sized sleeve 450
therebetween to provide a reservoir capable of holding a larger
volume of paint if required.
[0155] As a result, one size of inner container 409', lid 410' and
outer container 408' can be employed for assembly with different
sizes of sleeve 450 to produce any desired volume of reservoir. In
this way, the volume of the reservoir can be altered as desired
using common components that simplifies manufacture, supply,
storage and assembly of the paint reservoir for a variety of
different uses.
[0156] In the arrangement shown in FIGS. 32 and 33, the lid 410' is
provided with the connector tube 415' and filler opening 430'. A
modification of this arrangement is shown in FIG. 34 in which the
filler opening 430'' is re-positioned from the lid 410'' to the
wall of the extension sleeve 450''. This may allow easier access to
the filler opening 430'' when it is desired to add paint to the
reservoir. Also, manufacture of the lid 410'' is simplified.
[0157] As will now be appreciated, the present invention provides
apparatus for spraying a liquid having a collapsible reservoir
connected to a spray gun wherein liquid can be added to the
reservoir while it is attached to the spray gun. Other arrangements
of the fluid inlet for adding liquid to the reservoir while
attached to the spray gun will be apparent to those skilled in the
art and are deemed within the scope of this invention.
[0158] It will also be appreciated that the exemplary embodiments
described herein are intended to illustrate the diverse range and
application of the invention and that features of the embodiments
may be employed separately or in combination with any other
features of the same or different embodiments.
[0159] Moreover, while the exemplary embodiments described and
illustrated are believed to represent the best means currently
known to the applicant, it will be understood that the invention is
not limited thereto and that various modifications and improvements
can be made within the spirit and scope of the invention as
generally described herein.
[0160] Finally, as used herein, the term "liquid" refers to all
forms of flowable materials that can be applied to a surface using
a spray gun (whether or not they are intended to colour the
surface) including (without limitation) paints, primers, base
coats, lacquers, varnishes and similar paint-like materials as well
as other materials such as adhesives, sealers, fillers, putties,
powder coatings, blasting powders, abrasive slurries, mould release
agents and foundry dressings which may be applied in atomised or
non-atomised form depending on the properties and/or the intended
application of the material and the term "liquid" is to be
construed accordingly.
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